This plugin is actually a additional ajax script on top of GreaseMonkey AddOn. Though GreaseMonkey is available for IE, FireFox, Chrome, etc, this one works well with FireFox (as far as i tested it). So, the following step by step procedure will help you to install this plugin on FireFox browser.
But, whats this Plugin all about???
Target is the "Plan My Travel" page on IRCTC site. The first step to book any ticket, is to find out the trains running between our travel route and then check on availability on those trains. We do this in IRCTC page, by entering the source and destination stations, date of travel etc. and hitting "Find Trains". Now the page shows the list of trains that run between the stations on that day. So far, so good. Now, to book tickets on a train, the we select a train and hit "Book Ticket", if we know for sure that tickets will be available for that train. However, typically we need to check availability of tickets before proceeding to book them. The page makes it frustratingly difficult to do that - checking availability for a train takes two clicks, and worse, the availability information shows up on a new window, forcing the user to switch back and forth between the windows.
So, how about the listing the availability on the same page, where it shows the list of trains? thats what this plugin does, without any extra load on that page.
Without any delay, follow these steps to install it on FireFox browser.
Step 1: Install GreaseMonkey AddOn in Firefox, if you haven't done before.(Note: If you already have this AddOn installed, skip these steps and directly goto Step 5) Click Here to go to the GreaseMonkey AddOn Page for FireFox. (https://addons.mozilla.org/en-US/firefox/addon/748/)
Step 2: Click on "Add to Firefox" button on that AddOn page. This pops-up the "Install AddOn" screen Click on "Install" Button to start the installation of this Addon.
Step 3: Once the installation of AddOn is complete, for this AddOn to take effect, you need to Restart Firefox Browser. Click on the "Restart FireFox" button.
Step 4: Once the restart of the FireFox Browser is complete, it displays the confirmation of successful installation of GreaseMonkey Plugin.
Step 5: Install the user script for adding this new column in the List of Trains table in IRCTC site. Click here to install. (http://senthilthecoder.com/software/irctcscripts/ajaxavailability.user.js) This pops-up AJAXAvailabilty user script. Click on "Install" button to install the user script.
Step 6: Once the AJAX Availability user script is installed successfully, you'll get the message in the right bottom corner on the status bar of the FireFox browser.
Step 7: Access the IRCTC page now, you'll get the Availability column added, just like below:
Thanks to: https://msmvps.com/blogs/senthil/archive/2007/11/10/greasemonkeying-around-with-irctc.aspx
(note: thats not me... :) )